It's not $500 off, it's not anything off actually. You get "up to $500" if you trade in a qualifying phone, which means you aren't getting any discounts at all. Some of the trade in phones seem like a good deal, $500 for a S7 or Note 5 seem very good and better than anything you would get selling it on swappa or CL. $700 seems like more of a fair price for the Note 9 IMO, but I don't think I'd jump on one until it was $500 or so, which will most likely be in the not too distant future when a huge glut of "free" Note 9's from BOGO's appear there. Actually I don't think I'd jump on one anyhow due to the curved screen and all of the privacy issues, but it still is a decent price for others.
I've said it before, I still don't understand why Samsung just doesn't undercut everyone else and release the phone for say $699 or even $799 instead of all these BOGO's which no one really likes because you have to deal with bill credits over 24+ months, so they are just like the old days when we would sign a 2 year contract for a discount. The free accessories are ok I suppose, but personally I'd rather have their cash value deducted from the phone. Somehow I just highly doubt your typical consumer says "hey it's $1000 it must be high quality, let me buy it right away". That perceived value doesn't mean squat if you are giving them away.